Hold-down devices for side trimming shears



June 7, 1955 c. T. LANsTRoM 2,710,062

HOLD-DOWN DEvIES FOR SIDE TRIMMING SHEARS Filed Feb. 8, 1952 2sheets-sheet 1 INVENToR: Cna 7,'4/1/57/90/14,

June 7,l 1955 c. T. LANsTRoM 2,710,062

HOLD-DOWN DEVICES FOR SIDE TRIMMING sHEARs Filed Feb. 8, 1952 2Sheets-Sheet 2 f FISE- HOLD-DOWN DEVICES FR SIDE TRIMMING SHEARS Cari T.Lanstrom, Concord, Calif., assignor t United States Steel Corporation, acorporation of New Jersey Application February 8, 19452, Serial No.270,680

7 Claims. (Cl. 164-60) This invention relates to improved devices forholding down metal strip while passing through side trimming shears.

The practice in manufacturing metal strip is to trim its side edges sothat they are uniform in the finished product. This side trimming isaccomplished by feeding the strip past shears which have rotatableknives situated adjacent each side edge of the strip. Such shearsrequire hold-down devices for retaining the strip, and previoushold-downs with which I am familiar have been in the form of lixed shoesthat contact both the upper and lower faces of the strip. For steelstrip the shoes are of a softer metal, such as brass, in order not toscratch the strip surface. These shoes have the disadvantage that on oneface of the strip small particles produced during cutting tend to lodgebetween the shoe and the strip surface and seriously scratch the latter.o minimize the chance for such particles to get under the shoes, theshoes are spaced a considerable distance inwardly f of the shear knives,where they do not retain the strip properly and do not always preventcobbling and torn edges.

An object of the present invention is to provide improved hold-downdevices which overcome the foregoing disadvantages; that is, they canengage the strip closely adjacent its edges to furnish proper holdingaction and yet eliminate the possibility of scratching the stripsurface.

A more specific object is to provide improv-ed holddown devices whichinclude adjustably mounted rotatable wheels engageable with the upperface of the strip adjacent its opposite side edges, whereby anyparticles caught on the wheel surface at most dent the strip surfacewithout scratching it and the particles easily can be removed. p

. In accomplishing these and other objects of the invention', I haveprovided improved details of structure, a

preferred form of which is shown in the accompanying` drawings, inwhich:

Figure 1 is a top plan View of side trimming shears which are equippedwith an improved hold-down device embodying features of thepresentinvention;

Figure 2 is a front elevational view of the structure shown in Figure 1;

Figure 3 is a vertical sectional view taken substantially on line III-IHof Figure 1;

Figure 4 is a horizontal sectional view taken substantially on lineIV-IV of Figure 5;

Figure 5 is a vertical sectional view taken substantially on line V-V ofFigure 4; and

Figure 6 is a vertical sectional view taken substantially on line VI-VIof Figure 5.

Figures l and 2 show somewhat schematically a pair of side trimmingshears which include spaced apart housings 10 and 12. One or both ofthese housings are adjustable toward and away from the center line ofthe strip to accommodate strip of different widths. Each housing carrieslower and upper rotatable knives 13 and 14. A continuous strip S is fedthrough the space between said housings and is supported on itsunderside by the usual shoes 15 (Figure 2). The shear and feed means arenot United States Patent C shown in detail since they can be of anystandard or desired construction. The lower knives are offset inwardlywith respect to the upper knives. Consequently any loose cuttings orother particles beneath the strip tend to move outwardly away from thestrip and do not lodge between the shoes 15 and the bottom surface ofthe strip. The lower knives in fact act as barriers against suchparticles reaching the shoes. However, loose particles above the striptend to move inwardly over the strip surface where they ordinarily canlodge under the hold-down device.

The hold-down device of the present invention comprises brackets 16 and17 mounted on the entry ends of the two housings 10 and 12. A pair ofrods 18 and 19 are iixedly supported in bracket 16 and adjustablysupported in bracket 17 so as not to interfere with sidewise adjustmentof the housings. Three supporting arms 20, 21 and 22 are slidablymounted on rods 18 and 19. Adjusting bolts 24 are Xed to brackets 16 and17 and are adjustably received in openings through the outside arms and22 (Figure 3). Positioning nuts 25 are threadedly engaged with saidbolts for holding the arms in adjusted position. Once the outside armsare adjusted with respect to the housings, it is unnecessary to varytheir adjustment except to position them for knives of differentthickness, although of course these arms move with the housings as thelatter are adjusted to accommodate strip of different widths. Duringsuch adjustment arm 22 can move back and forth along the rods 18 and 19with the housing 12. The central arm 21 has a locking screw 26engageable with one of the rods 1S 0r 19 (Figure l). Normally this armis adjusted to a position over the center line of the strip, whichposition varies with the width of strip.

Each of the arms 20, 21 and 22 extends from the rodsv 18 and 19 to aposition over the axes of rotation of the knives 13 and 14, and eachcarries a wheel 27, 2S and 29 respectively. Each of the wheels has atire that en gages the strip S opposite one of the shoes 15. As shown inFigure 6, the line of contact between the tire 30 of the wheel 29 andthe upper surface of the strip S lies in the same vertical plane a-a asthe axes of rotation of the upper and lower knives. The lines of contactbetween the tires 30 of the wheels 27 and 28 and the strip also lie inthis same vertical plane. The tires are of smooth non-abrasive material,such as hard ber, and do not scratch the strip surface. The Aouter facesof the outside wheels 27 and 29 are dished to receive the knife hubs asshown in Figure 5, and the tires are relatively wide to furnish arelatively long line of contact with the strip.

Figures 4, 5 and 6 show in detail the mounting means for the wheel 29 onthe arm 22, the mounting means for the wheels on the other arms beingsimilar. This mounting means includes a vertically movable slide 31which rides in a groove 32 in the face of the arm, where it is held bygibs 33. The slide carries a wheel bearing 34 which extends through aslot 35 in the arm and in which the wheel shaft is rotatably journaled.l The upper part of the slide carries a nut 36. An adjusting screw 37 isjournaled in the upper part of the arms and threadedly engages nut 36,so that manual rotation of the screw raises or lowers the slide, wheelbearing and wheel.

In setting up the hold-down device, the outside arms 20 and 22 areadjusted on the rods 18 and 19 for the particular knives used in theshears. The adjustment is such that the outside wheels 27 and 29 lieclosely adjacent the upper knives 14 and preferably their edges overlapthe edges of the lower knives 13, as Figure 5 shows. Next the housings10 and 12 are positioned so that the spacing between their knivescorrespond with the desired strip width in accordance with usualpractice. The central arm 21 then is moved to a position such that itswheel 28 lies directly over the center line of the strip. The threewheels are raised by rotation of their adjusting screws 37 and the stripis threaded through the shears and holddown. The wheels then are loweredby rotation of screws 37 in the opposite direction until they bearagainst the upper surface of the strip with the desired pressure. Thestrip now can be fed through the shears.

It is seen that the three wheels function as hold-downs for the stripand that the outside wheels are situated closely adjacent the kniveswhere they prevent cobbles and torn edges. Any cuttings from the stripwhich come against the wheel surfaces either are thrown off bycentrifugal force or easily can be cleaned od. There is no likelihood ofsuch particles scratching the strip surface.

While I have shown and described only a single embodirnent of theinvention, it is apparent that modifications may arise. Therefore, I donot wish to be limited to the disclosure set forth but only by the scopeof the appended claims.

I claim:

1. In a side trimming shear for metal strip which includes a pair ofspaced apart housings, lower and upper rotatable knives carried by eachof said housings and adapted to trim the strip edges, and shoes forsupporting the strip on its underside, the combination with saidhousings of a hold-down device which comprises support means carried bythe housings, a pair of arms carried by said support means, each of saidarms being adjacent a different one of said housings and spaced inwardlythereof, wheel bearings carried by each of said arms, means on each ofsaid arms for individually adjusting the wheel bearing thereon in avertical direction, wheels mounted in each of said wheel bearings forrotation on axes which are independent of the axes of rotation of saidknives, said wheels having smooth non-abrasive surfaces engageable withthe upper face of the strip opposite said shoes and closely adjacentsaid knives, and additional means engageable with the upper face of thestrip at its center line.

2. A combination as defined in claim 1 in which said additional meansincludes an arm carried by said support means, and a wheel rotatablysupported by said last named arm.

3. In a side trimming shear for metal strip which includes a pair ofspaced apart housings adjustable toward and away from each other, lowerand upper rotatable knives carried by each of said housings and adaptedto trim the strip edges, and shoes for supporting the strip on itsunderside, the combination with said housings of a hold-down devicewhich comprises a support extending therebetween and being adjustablymounted on one of said housings, outside arms and a central arm mountedon said support and extending over the knife axes, wheel bearingscarried by each of said arms, means on each of said arms forindividually adjusting the wheel bearing thereon in a verticaldirection, and wheels carried by said wheel bearings for rotation onaxes which are independent of the axes of rotation of said knives, saidwheels having smooth non-abrasive surfaces engageable with the upperface of the strip opposite said shoes, the wheels on said outside armslying closely adjacent said upper knives, said central arm beingadjustable along said support to enable the wheel thereon to be placedover the center line of the strip.

4. In a side trimming shear for metal strip which includes a pair ofspaced apart housings adjustable toward and away from each other, lowerand upper rotatable knives carried by cach of said housings and adaptedto trim the strip edges, and shoes for supporting the strip on itsunderside, the combination with said housings of a hold-down devicewhich comprises a pair of rods xed to one housing and adjustably mountedon the other and extending between the two housings, outside arms and acentral arm mounted on said rods for adjustment therealong and extendingover the knife axes, wheel bearings carried by each of said arms, meanson each of said arms for individually adjusting the wheel bearingthereon in a vertical direction, and wheels carried by said wheelbearings for rotation on axes which are independent of the axes ofrotation of said knives, said wheels having smooth non-abrasive surfacesengageable with the upper face of the strip opposite said shoes, thewheels on said outside arms lying closely adjacent said upper knives andhaving their outer faces dished to receive the knife hubs, adjustment ofsaid central arrn along said rods enabling the wheel thereon to beplaced over the center line of the strip.

5. In a side trimming shear for metal strip which in cludes a pair ofspaced apart housings adjustable toward and away from each other, lowerand upper rotatable knives carried by each of said housings and adaptedto trim the strip edges, said lower knives being odset inwardly withrespect to said upper knives, and shoes for supporting the strip on itsunderside, the combination with said housings of a hold-down devicewhich com. prises a pair of rods fixed to one housing and adjustablymounted on the other and extending between the two housings, outsidearms and a central arm mounted on said rods for adjustment therealongand extending over the knife axes, wheel bearings carried by each ofsaid arms, means on each of said arms for individually adjusting thewheel bearing thereon in a vertical direction, and wheels carried bysaid wheel bearings for rotation on axes which are independent or" theaxes of rotation of said knives, said wheels having smooth non-abrasivesurfaces engageable with the upper face of the strip opposite saidshoes, the wheels carried by said outside arms lying closely adjacentsaid upper knives and having their outer faces dished to receive theknife hubs and their edges overlapping said lower knives, adjustment ofsaid central arm along said rods enabling the wheel thereon to be placedover the center line of the strip.

6. In a side trimming shear for metal strip which includes a pair ofspaced apart housings adjustable toward and away from each other, lowerand upper rotatable knives carried by each of said housings and adaptedto trim the strip edges, and shoes for supporting the strip on itsunderside, the combination with said housings of a hold-down devicewhich comprises a support extending therebetween and being adjustablymounted on one of said housings, outside arms and a central arm mountedon said support and extending over the knife axes and having verticalslideways formed therein, wheel bearings mounted in said slideways forindividual vertical adjustment, rotatable adjusting screws connectingeach of said arms with the bearings mounted therein, and wheels carriedby said wheel bearings for rotation on axes which are independent of theaxes of rotation of said knives, said wheels having smooth non-abrasivesurfaces engageable with the upper face of the strip opposite saidshoes, the wheels on the outside arms lying closely adjacent said upperknives, said central arm being adjustable along said support to enablethe wheel carried thereby to be placed over the center line of thestrip,

7. A combination as dened in claim 6 in which the wheels carried by saidoutside arms have dished outer faces receiving the knife hubs.

References Cited in the tile of this patent UNITED STATES PATENTS824,694 Irwin June 26, 1906 1,291,931 Kornas Ian. 2l, 1919 2,014,248Evans Sept. 10, 1935 2,097,636 Moore Nov. 2, 1937 2,204,904 Moore June18, 1940 FOREIGN PATENTS 371,794 Great Britain Apr. 28, 1932

